Symptoms

Pubic lice cause itching in the area covered by pubic hair. Itching often gets worse at night. The itching may start soon after getting infected with lice, or it may not start for up to 2 to 4 weeks after contact.

Other symptoms can include:

Local skin reactions to the bites that causes skin to turn red or bluish-gray

Exams and Tests

Small gray-white oval eggs (nits) attached to the hair shafts in the outer genital area.

Scratch marks or signs of a skin infection.

Because pubic lice may cause an eye infection in young children, eyelashes should be looked at with a high-powered magnifying glass.

Adult lice are easy to identify with a special magnifying device called a dermoscope. Pubic lice are often referred to as "the crabs" because of their appearance.

Teenagers with pubic lice may need to be tested for other sexually transmitted infections (STIs).

Treatment

MEDICINES

Pubic lice are often treated with medicines that contain a substance called permethrin. To use this medicine:

Thoroughly work the medicine into your pubic hair and surrounding area. Leave it on for at least 5 to 10 minutes, or as directed by your provider.

Rinse well.

Comb your pubic hair with a fine-toothed comb to remove eggs (nits). Applying vinegar to pubic hair before combing may help loosen the nits.

Most people need only one treatment. If a second treatment is needed, it should be done 4 days to 1 week later.

Over-the-counter medicines to treat lice include Rid, Nix, LiceMD, among others. Malathione lotion is another option.

OTHER CARE

While you are treating pubic lice:

Wash and dry all clothing and bedding in hot water.

Spray items that cannot be washed with a medicated spray that you can buy at the store. You can also seal items in plastic bags for 10 to 14 days to smother the lice.

Makes sure anyone with whom you have had sexual contact or shared a bed is treated at the same time.

People with pubic lice should be checked for other sexually-transmitted infections when lice are discovered.

Outlook (Prognosis)

The proper treatment, including thorough cleaning, should get rid of the lice.

Scratching can make the skin raw or cause a skin infection.

When to Contact a Medical Professional

Call for an appointment with your provider if:

You or your sexual partner has symptoms of pubic lice

You try over-the-counter lice treatments and they are not effective

Your symptoms continue after treatment

Prevention

Avoid sexual or intimate contact with people you who have pubic lice until they have been treated.

Bathe or shower often and keep your bedding clean. Avoid trying on bathing suits while you are shopping. If you must try on swimwear, be sure to wear your underwear. This may prevent you from getting or spreading pubic lice.

Crab louse, female - illustration

This is a photomicrograph of a female pubic louse. The condition known as "crabs" is so named because of the resemblance of a pubic louse to a crab. The bodies of pubic lice are shorter and rounder than those of head lice. (Image courtesy of the Centers for Disease Control and Prevention.)

Crab louse, female

illustration

Pubic louse-male - illustration

This is a photomicrograph of a male pubic louse. The condition known as "crabs" is so named because of the resemblance of a pubic louse to a crab. The bodies of pubic lice are shorter and rounder than those of head lice.

Pubic louse-male

illustration

Crab lice - illustration

This photograph shows pubic lice clinging to individual hairs (the small, whitish specks). The reddish, crusted areas with scabs (excoriated areas) are caused by scratching. (Image courtesy of the Centers for Disease Control and Prevention.)

Crab lice

illustration

Head louse and pubic louse - illustration

This picture compares the relative size and shape of the head louse and the pubic louse.

Head louse and pubic louse

illustration

Crab louse, female - illustration

This is a photomicrograph of a female pubic louse. The condition known as "crabs" is so named because of the resemblance of a pubic louse to a crab. The bodies of pubic lice are shorter and rounder than those of head lice. (Image courtesy of the Centers for Disease Control and Prevention.)

Crab louse, female

illustration

Pubic louse-male - illustration

This is a photomicrograph of a male pubic louse. The condition known as "crabs" is so named because of the resemblance of a pubic louse to a crab. The bodies of pubic lice are shorter and rounder than those of head lice.

Pubic louse-male

illustration

Crab lice - illustration

This photograph shows pubic lice clinging to individual hairs (the small, whitish specks). The reddish, crusted areas with scabs (excoriated areas) are caused by scratching. (Image courtesy of the Centers for Disease Control and Prevention.)

Crab lice

illustration

Head louse and pubic louse - illustration

This picture compares the relative size and shape of the head louse and the pubic louse.